1. Field
The present disclosure relates to an actuator and a driving apparatus of a camera module.
2. Description of Related Art
Portable communication devices such as mobile phones, personal digital assistants (PDAs), portable PCs have the ability to send video data, as well as sending text or voice data. Recently, camera modules have also been incorporated in portable communication terminals to allow for video data to be captured as well as video chatting.
A camera module generally includes a lens barrel having a lens, a housing accommodating the lens barrel, and an image sensor converting an image of a subject into an electrical signal. In an example, a short focal length type camera module imaging an object at a fixed focal point may be employed as the camera module. Recently, in line with the advancement of technology, a camera module including an actuator available for auto-focusing has been employed. In addition, the camera module may also employ an actuator for optical image stabilization (OIS) to reduce a degradation of resolution due to camera shake.
A reduction in the thickness of mobile devices limits a movement range of a lens barrel of a camera module in an optical axis direction. When a control gain is uniformly maintained in the camera module, which is limited in terms of movement range, a rise time is increased due to frictional force, or overshoot may occur due to acceleration.